DHAKA: Republican ex-presidential candidate Mitt Romney has urged his party to reject Donald Trump, reportedly calling the front-runner a "phony" and "fraud".

Romney accuses Trump of "playing the American public for suckers", in a planned speech leaked to the media, reports the BBC.

Trump has meanwhile mocked Romney on Twitter as a "failed candidate" who should not advise on getting elected.

Many senior Republicans are alarmed at the prospect of Trump securing the nomination for November's election.

In the latest attack from top figures in the party, several members of the Republican national security community wrote an open letter describing Trump's "vision of American influence and power in the world" as "wildly inconsistent and unmoored in principle".

"He swings from isolationism to military adventurism within the space of one sentence," the letter said.

Trump has sought to present himself as a "unifier", after his victories in seven states on so-called Super Tuesday consolidated his position at the front of the race for his party's nomination.

Romney, who has been a fierce critic of Trump, is expected to warn in his speech on Thursday that his policies are a threat to the Republican party and to the country as a whole.

"Here's what I know: Donald Trump is a phony, a fraud," Romney says, according to a leaked transcript of his remarks.

"His promises are as worthless as a degree from Trump University," he is quoted as saying.

Romney will also warn that the nomination of Trump would pave the way to the presidency for Democratic rival Hillary Clinton.

Trump meanwhile accused Romney of having run "one of the worst races in presidential history" and "working with the establishment" to prevent a Republican win.

Romney lost the 2012 election to President Barack Obama.

BDST: 2014 HRS, MAR 03, 2016
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